Diesel engines have fuel injectors that inject fuel into a highly pressurized combustion chamber just before a controlled explosion of the fuel. The injector is typically located in a cylinder head of the motor and a tight sealing relationship must be attained between the injector and the cylinder head to prevent the pressurized gases in the combustion chamber from leaking past the fuel injector. Therefore, the fit between a bore in the cylinder head for the fuel injector and the fuel injector is typically quite close. An O-ring normally assists in providing the seal. After they have been in service for an extended period of time, the fuel injectors require replacement. However, with use, the fuel injectors require considerable force to be removed from the cylinder head because the O-ring becomes hard with time and carbon deposits build up upon the fuel injector and cylinder head and serve to bond the cylinder head and fuel injector together.
In the past, different tools have been used to remove the fuel injectors from the cylinder head with varying results. For example, one method of removing the fuel injectors was to thread a slide hammer onto the end of the fuel injector to remove the fuel injector. A slide hammer is essentially a large weight, in a form that can be gripped by a user, with a bore in the center. A long rod is inserted through the bore in the weight and the rod further comprises a rod head that will not extend through the bore of the weight. The user attaches the end of the rod to the fuel injector and repeatedly slams the weight against the rod head to remove the fuel injector.
As can be understood, a slide hammer requires a great amount of force to be exerted by the operator. Accidents with slide hammers are common, such as pinched and broken fingers and injuries from operators losing their balance while operating the slide hammer. Additionally, considerable time may be required to extract stubborn fuel injectors from cylinder heads and, in some instances, the slide hammer simply cannot exert enough force to remove the fuel injector and the entire cylinder head must be removed and replaced, which is a time-consuming and expensive operation.
U.S. Pat. No. 4,293,992 to Webb discloses a tool for removing fuel injectors from diesel engines without damaging any adjacent component parts or user's hands. The invention comprises an elongated member having a U-shaped injector engaging member at one end. The elongated member has a locating pin which is adapted to fit inside one of several bolt holes along side a fuel injector in a diesel engine. The locating pin serves as a pivot for the mechanic to manually lever the injector loose from the diesel engine.
U.S. Pat. No. 5,020,203 to Rix describes a high pressure fuel injector installation and removal tool for use on internal combustion engines which can be used to precisely locate the fuel injector during installation. The installation tool provides an alignment guide, as well as the mechanical impulse necessary to fully seat the fuel injector in the base cavity. The alignment guide forms a location skirt with projected ears around the perimeter of the fuel injector during the installation procedure and thus provides a means to assure sufficient clearance between the fuel injector and surrounding components without need for visual alignment.
U.S. Pat. No. 6,978,527 to Oser teaches a fuel injector remover for removing a fuel injector from a cylinder head wherein the fuel injector is located within a counterbore of the cylinder head. The remover includes a primer mover having a piston defining a central bore. A snout portion is attached to the prime mover and defines a central bore. The snout portion has a first end attached to the prime mover and a second end defining a tapered portion sized such that when the tapered portion abuts an outer diameter of the cylinder head counterbore, the prime mover is centered over the fuel injector. A puller rod extends through the central bores of the piston and the snout. A thumbscrew is provided for attachment to the threaded end of the puller rod after the puller rod has been inserted through the central bore of the cylinder.
The foregoing patents reflect the current state of the art of which the present inventor is aware. Reference to, and discussion of, these patents is intended to aid in discharging Applicant's acknowledged duty of candor in disclosing information that may be relevant to the examination of claims to the present invention. However, it is respectfully submitted that none of the above-indicated patents disclose, teach, suggest, show, or otherwise render obvious, either singly or when considered in combination, the invention described and claimed herein.